Brushless doubly-fed induction machine with rotating power electronic converter for wind power applications

This paper introduces, simulates and analyzes a new topology of a brushless doubly-fed induction machine with rotating power electronic converter for wind power applications. Topology consists of two machines, one is the main machine which is directly connected to the grid while the second machine is the auxiliary machine which handles the slip power. The rotor of the two machines are connected via a power electronic converter which is mounted on the shaft and rotates with it. The steady state equivalent circuit of the two machine configuration is developed and analyzed. It is shown through simulations that the stator terminals of the machine can be operated at a unity power factor for variable speed range. Furthermore, it is shown that the presented system operates at a high efficiency at rated load and unity power factor.